Transmission Network Expansion Planning (TNEP) is one of the major components of the electric power industry. In the deregulated power systems, transmission systems provide the required environment for the competition among the power market participants. In this paper a mathematical model and a methodology are presented to solve the TNEP problem with security consideration and high penetration of wind energy and uncertainties such as load and bid of producers in deregulated electricity markets. In proposed model construction cost of new network, congestion cost, paid cost of unsupplied energy and also the cost of security has been considered. Considering the cost of operation in normal mode and also observing the loading rate limits on generators at event are the benefits of proposed method. To expand the transmission network a sample test system with use of appropriate optimization methods in the presence of wind energy and network uncertainties are considered. In this context we will choose the best scenario in terms of economic and technical consideration to be introduced. The Planning methodology has been demonstrated on the modified IEEE 24-bus test system to show the feasibility and capabilities of the proposed algorithm.
